Lipases are enzymes that hydrolyze tri-, di-, and mono-glycerides. Triglycerides of long-chain fatty acids are the natural substrates of lipases and are insoluble in water. Lipases are characterized by their ability to rapidly catalyze the hydrolysis of ester bonds at the interface between the insoluble substrate phase and the aqueous phase in which the enzyme is soluble. The ability to catalyze hydrolysis of insoluble long-chain fatty acid esters distinguishes lipases from other esterases which catalyze hydrolysis of soluble esters in preference to insoluble esters.
Lipases are produced by plants, animals, and microbial species. A wide variety of microorganisms (including yeasts, molds and bacteria) are sources of lipases. Microbial lipases from the yeasts, Candida and Torulopsis, molds such as Rhizopus, Penicillium, Aspergillus, Geotrichum and Mucor and bacteria of the genera Pseudomonas, Achromobacter, and Staphylococcus have been found.
Most of these microbial enzymes are extracellular and in some instances inducible with various substrates. The formation of the enzyme is feedback regulated by mono- and di-saccharide and glycerol in the growth medium. Some microbial lipases are glycosylated and the sugar moiety is thought to facilitate the passage of the enzyme through the cell wall into the growth medium.
There are a number of industrial applications for microbial lipases. They are the following: